162BOTANY.description of Mr. Watson.—Plate IV. Figure 6. A branch, natural size7. A disk-flower. 8. Chaff of disk-flower. 9. Ray-flower. 10. Sectionthrough receptacle. All except the branch enlarged 10-20 diameters. Helianthus petiolaeis, Nutt.—Tall, erect, hispid; leaves scabrous(lower sometimes opposite, upper alternate), ovate or ovate-lanceolate,irregulariy serrate-acuminate; petioles long (but variable in length);peduncles terminal; heads large; involucral scales lanceolate or broadlylanceolate, acute; disk-coroUa hairy at base; achenia viUous; pappus of"two chaffy awns"; rays large, over an inch long.—Southern Arizona,Nevada, and Colorado. Helianthus annuus, L. (Helianthus lenticularis, Dougl, see Gray,Fl Cal. 1, p. 353; also H. lenticularis, Dougl. vol. v, King's Report, andPreliminary Report of Mr. Watson in Wheeler's Survey, Washington,1874.)—Utah and Colorado. Helianthus Nuttallii, T. & G.—Nevada and San Luis VaUey, Colo¬rado, with broader leaves (548). Helianthus giganteus, L., var. Utahensis, Eaton —Utah. Helianthella unifloea, T. & G.—South Park, Colorado (546). AcTiNOMEEis* Weightii, Gray (Pl. Fendl. p. 85).—Erect, somewhatbranching; stems canescently hispid; leaves sessile or slightly decurrent,lower opposite, upper alternate, oblong or lance-ovate, irregularly andstrongly serrate, thick, scabrous, and distinctly veined, especially beneath;heads on naked peduncles (6-12' long), medium-sized; scales of the invo¬lucre in 2-4 series, with a short stout pubescence, outer ones shorter,oblong and obtuse, inner lanceolate and acute; rays short, entire orslightly toothed (or sometimes none). Achenia of the disk cuneate-oblong,with a distinct wing extending half-way down the achenium on either side, " Actinomeris, Nutt.—Heads heterogamous, radiate ; flowers of the ray neutral and in a singleseries; disk-flowers hermaphrodite, fertile ; heads sometimes, by the deficiency of the rays, homogamous.Involucre hemispherical or campanulate; bracts 2-3-8eried,'unequal, short or the outer ones elongatedaud foliaceous. Eeceptacle convex or at length conical, covered with chaff, which emhraces the disk-flowers. Eay-coroUas ligulate, spreading, entire or 2-3-toothed ; disk-flowers regular, with a short tube;limb elongated-cylindrical, 5-cleft at top. Anthers entire at base. Branches of the style iu the disk-flowers terminated by acute appendages. Achenia laterally compressed, with margins attenuated anddistiuctly winged. Pappus usually of two persistent awns.—Scabrous herbs. Leaves opposite oralternate, petioled, sessile, or decurrent. Heads middle-sized, solitary, and with long peduncles orcorymbose-paniculate.—Benth. & Hooic.